﻿using System;
using System.IO;
using System.Web;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;
using System.Xml.Serialization;
using XQ.Framework.core;

namespace XQ.Framework.io
{
    /// <summary>
    /// IO帮助类
    /// </summary>
    public class IOHelper
    {
        public static readonly string[] TEXT_EXTENSION = new string[] { ".txt",".css",".js",".log",".py" };

        public static bool IsFileExtesionAllowed(string name, string[] allow_list)
        {
            for (int i = 0; i < allow_list.Length; ++i)
            {
                if (name.ToLower().EndsWith(allow_list[i].ToLower()))
                {
                    return true;
                }
            }
            return false;
        }
        public static FileAttributes getFileAttr(string file_path)
        {
            return File.GetAttributes(file_path);
        }
        public static FileStream WritePostFileToFileStreamAndCloseStream(HttpPostedFile file, FileStream stream)
        {
            return WritePostFileToStreamAndCloseStream<FileStream>(file, stream);
        }
        public static T WritePostFileToStreamAndCloseStream<T>(HttpPostedFile file, T stream) where T : Stream
        {
            if (file == null || file.InputStream == null || stream == null) { return null; }
            try
            {
                byte[] buffer = new byte[1024 * 1024];
                int len = 0;
                while ((len = file.InputStream.Read(buffer, 0, buffer.Length)) > 0)
                {
                    stream.Write(buffer, 0, len);
                }
                stream.Flush();
                return stream;
            }
            catch
            {
                return null;
            }
            finally
            {
                closeStream(stream, file.InputStream);
            }
        }
        public static byte[] getPostFileBytes(HttpPostedFile postFile)
        {
            if (postFile == null || postFile.InputStream == null)
            {
                return null;
            }
            try
            {
                byte[] b = new byte[postFile.InputStream.Length];
                postFile.InputStream.Read(b, 0, b.Length);
                return b;
            }
            catch { return null; }
            finally
            {
                closeStream(postFile.InputStream);
            }
        }

        public static byte[] getFileBytes(string file_path)
        {
            FileStream fs = null;
            try
            {
                if (!File.Exists(file_path))
                {
                    return null;
                }
                FileInfo f = new FileInfo(file_path);
                fs = f.Open(FileMode.Open, FileAccess.Read);
                byte[] bb = new byte[fs.Length];
                fs.Read(bb, 0, bb.Length);
                return bb;
            }
            catch
            {
                return null;
            }
            finally
            {
                closeStream(fs);
            }
        }

        public static void closeStream(params Stream[] stms)
        {
            for (int i = 0; i < stms.Length; ++i)
            {
                if (stms[i] != null)
                {
                    stms[i].Close();
                    stms[i].Dispose();
                }
            }
        }

        public static void closeStreamWriter(params TextWriter[] writers)
        {
            for (int i = 0; i < writers.Length; ++i)
            {
                if (writers[i] != null)
                {
                    writers[i].Close();
                    writers[i].Dispose();
                }
            }
        }

        public static void closeStreamReader(params TextReader[] readers)
        {
            for (int i = 0; i < readers.Length; ++i)
            {
                if (readers[i] != null)
                {
                    readers[i].Close();
                    readers[i].Dispose();
                }
            }
        }

        public static string getStringContentFromFile(string filePath)
        {
            StringBuilder str = new StringBuilder();
            StreamReader streamreader = null;
            try
            {
                FileInfo fi = new FileInfo(filePath);
                if (!fi.Exists || !IsFileExtesionAllowed(fi.FullName, IOHelper.TEXT_EXTENSION))
                {
                    return string.Empty;
                }
                streamreader = new StreamReader(fi.OpenRead(), Encoding.UTF8);
                char[] b = new char[1024 * 100];
                while (streamreader.Read(b, 0, b.Length) != 0)
                {
                    str.Append(b);
                }
                return str.ToString();
            }
            catch (Exception err)
            {
                return err.Message;
            }
            finally
            {
                if (streamreader != null)
                {
                    streamreader.Dispose();
                }
            }
        }

        public static string getFileExtension(string filename)
        {
            /*
            string[] filenamesplit = filename.Split('.');
            filename = filenamesplit[0];
            string file_extesion = "." + filenamesplit[filenamesplit.Length - 1].Trim().ToLower();*/
            return Path.GetExtension(filename);
        }

        public static string getDirectoryName(string path)
        {
            return Path.GetDirectoryName(path);
        }

        public static string GetSysPathSeparator()
        {
            return ConvertHelper.getString(Path.DirectorySeparatorChar);
        }

        public static class DirectoryHelper
        {
            public static bool Exists(string path)
            {
                return System.IO.Directory.Exists(path);
            }

            public static string[] ListFiles(string path)
            {
                if (DirectoryHelper.Exists(path))
                {
                    return Directory.GetFiles(path);
                }
                return null;
            }

            public static bool Delete(string path)
            {
                try
                {
                    if (!DirectoryHelper.Exists(path)) { return true; }
                    Directory.Delete(path);
                    return true;
                }
                catch
                {
                    return false;
                }
            }
            public static bool Create(string path)
            {
                try
                {
                    if (DirectoryHelper.Exists(path)) { return true; }
                    Directory.CreateDirectory(path);
                    return true;
                }
                catch
                {
                    return false;
                }
            }
        }

        public static class FileHelper
        {
            public static bool Exists(string path)
            {
                return System.IO.File.Exists(path);
            }

            public static bool Move(string path, string newPath, string filename)
            {
                return Move(path, newPath + filename);
            }

            public static bool Move(string path, string to)
            {
                try
                {
                    if (!FileHelper.Exists(path)) { return false; }
                    System.IO.File.Move(path, to);
                    return true;
                }
                catch
                {
                    return false;
                }
            }

            public static bool Copy(string path, string newPath, string filename)
            {
                return Copy(path, newPath + filename);
            }

            public static bool Copy(string path, string to)
            {
                try
                {
                    if (!FileHelper.Exists(path)) { return false; }
                    System.IO.File.Copy(path, to);
                    return true;
                }
                catch
                {
                    return false;
                }
            }

            public static bool Delete(string path)
            {
                try
                {
                    if (!FileHelper.Exists(path)) { return true; }
                    System.IO.File.Delete(path);
                    return true;
                }
                catch
                {
                    return false;
                }
            }
        }


        /// <summary>
        /// 获取文件的编码格式
        /// </summary>
        public class EncodingType
        {
            /// <summary>
            /// 给定文件的路径，读取文件的二进制数据，判断文件的编码类型
            /// </summary>
            /// <param name="FILE_NAME">文件路径</param>
            /// <returns>文件的编码类型</returns>
            public static System.Text.Encoding GetType(string FILE_NAME)
            {
                FileStream fs = new FileStream(FILE_NAME, FileMode.Open, FileAccess.Read);
                Encoding r = GetType(fs);
                fs.Close();
                return r;
            }

            /// <summary>
            /// 通过给定的文件流，判断文件的编码类型
            /// </summary>
            /// <param name="fs">文件流</param>
            /// <returns>文件的编码类型</returns>
            public static System.Text.Encoding GetType(FileStream fs)
            {
                byte[] Unicode = new byte[] { 0xFF, 0xFE, 0x41 };
                byte[] UnicodeBIG = new byte[] { 0xFE, 0xFF, 0x00 };
                byte[] UTF8 = new byte[] { 0xEF, 0xBB, 0xBF }; //带BOM
                Encoding reVal = Encoding.Default;

                BinaryReader r = new BinaryReader(fs, System.Text.Encoding.Default);
                int i;
                int.TryParse(fs.Length.ToString(), out i);
                byte[] ss = r.ReadBytes(i);
                if (IsUTF8Bytes(ss) || (ss[0] == 0xEF && ss[1] == 0xBB && ss[2] == 0xBF))
                {
                    reVal = Encoding.UTF8;
                }
                else if (ss[0] == 0xFE && ss[1] == 0xFF && ss[2] == 0x00)
                {
                    reVal = Encoding.BigEndianUnicode;
                }
                else if (ss[0] == 0xFF && ss[1] == 0xFE && ss[2] == 0x41)
                {
                    reVal = Encoding.Unicode;
                }
                r.Close();
                return reVal;
            }
            /// <summary>
            /// 判断是否是不带 BOM 的 UTF8 格式
            /// </summary>
            /// <param name="data"></param>
            /// <returns></returns>
            private static bool IsUTF8Bytes(byte[] data)
            {
                int charByteCounter = 1;　 //计算当前正分析的字符应还有的字节数
                byte curByte; //当前分析的字节.
                for (int i = 0; i < data.Length; i++)
                {
                    curByte = data[i];
                    if (charByteCounter == 1)
                    {
                        if (curByte >= 0x80)
                        {
                            //判断当前
                            while (((curByte <<= 1) & 0x80) != 0)
                            {
                                charByteCounter++;
                            }
                            //标记位首位若为非0 则至少以2个1开始 如:110XXXXX...........1111110X　
                            if (charByteCounter == 1 || charByteCounter > 6)
                            {
                                return false;
                            }
                        }
                    }
                    else
                    {
                        //若是UTF-8 此时第一位必须为1
                        if ((curByte & 0xC0) != 0x80)
                        {
                            return false;
                        }
                        charByteCounter--;
                    }
                }
                if (charByteCounter > 1)
                {
                    throw new Exception("非预期的byte格式");
                }
                return true;
            }
        }

    }
}
